1. Field of the Invention
This invention relates to selected 3,4-disubstituted-1,3,4-thiadiazoline-2,5-diones having two different aliphatic substituents on the nuclear nitrogen atoms. The 3-substituent is an aliphatic omega-carboxylate such as an alkanoate, alkenoate, alkynoate, or methylenebenzenealkanoate, and the 4-substituent is a hydroxy-substituted aliphatic group. The compounds are obtained by selective alkylation of the nitrogen atoms of 1,3,4-thiadiazoline-2,5-dione, and their biological properties resemble those of the prostaglandins and their derivatives.
2. Prior Art
3-Pyrazolidinones and pyrazolidines with biological activities resembling those of prostaglandins form the subject of U.S. Pat. 3,873,566. K. Rufenacht, Helv. Chim. Acta, 51, 518 (1968) has described the preparation of 4-hydroxymethyl- and 4-chloromethyl-2-methoxy-1,3,4-thiadiazol-5-ones and several of their derived dithiophosphoric acid esters as insecticides and acaricides by a different procedure from the present invention. S. W. Moje, Ph.D. thesis, University of Illinois, 1974, and S. W. Moje and P. Beak, J. Org. Chem., 39, 2951 (1974), disclose that both the mono- and di-potassium salts of 1,3,4-thiadiazoline-2,5-dione in DMF at 25.degree., on treatment with alkyl halides (benzyl bromide, methyl iodide, allyl bromide, and tert-butyl bromide) gave only the symmetrical dialkylated products. G. Ambrus et al, Prostaglandins, 10, No. 4, 661 (1975) disclose certain thiazole derivatives of prostaglandins. None of the references suggest the 3,4-disubstituted-1,3,4-thiadiazoline-2,5-diones of this invention.